U.S. patent number 5,270,378 [Application Number 07/966,458] was granted by the patent office on 1993-12-14 for acrylic surfactants and compositions containing those surfactants.
This patent grant is currently assigned to Minnesota Mining and Manufacturing Company. Invention is credited to David K. Johnson, Patricia M. Savu.
United States Patent |
5,270,378 |
Johnson , et al. |
December 14, 1993 |
**Please see images for:
( Certificate of Correction ) ** |
Acrylic surfactants and compositions containing those
surfactants
Abstract
A novel fluorochemical polymer surfactant reduces
disuniformities in polymeric coatings. The coating composition
comprising an organic solvent, an organic polymer compatible with
said solvent, and a coating aid comprising a fluorinated polymer
different from said polymer compatible with said solvent, said
fluorinated polymer having at least three different moieties within
the polymer chain derived from reactive monomers, the monomers
comprising a fluorochemical acrylate, a short-chain-alkyl acrylate,
and a polar monomer.
Inventors: |
Johnson; David K. (Brooklyn
Park, MN), Savu; Patricia M. (Ramsey, MN) |
Assignee: |
Minnesota Mining and Manufacturing
Company (St. Paul, MN)
|
Family
ID: |
25511442 |
Appl.
No.: |
07/966,458 |
Filed: |
October 26, 1992 |
Current U.S.
Class: |
524/520; 428/421;
428/457; 428/483; 524/507; 524/509; 524/514; 524/544; 526/245 |
Current CPC
Class: |
C09D
133/06 (20130101); C09D 133/14 (20130101); C09D
133/06 (20130101); C09D 133/14 (20130101); Y10T
428/31797 (20150401); Y10T 428/31678 (20150401); Y10T
428/3154 (20150401); C08L 2666/02 (20130101); C08L
2666/02 (20130101) |
Current International
Class: |
C09D
133/14 (20060101); C09D 133/06 (20060101); C08L
027/00 () |
Field of
Search: |
;524/520,544,507,509,514
;526/245 ;428/421,457,483 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Michl; Paul R.
Assistant Examiner: DeWitt; LaVonda
Attorney, Agent or Firm: Griswold; Gary L. Kirn; Walter N.
Litman; Mark A.
Claims
We claim:
1. A coating composition comprising an organic solvent, an organic
polymer compatible with said solvent, and a coating aid comprising
a fluorinated polymer different from said polymer compatible with
said solvent, said fluorinated polymer having at least three
different moieties within the polymer chain derived from reactive
monomers, the monomers comprising a fluorinated acrylate, a
short-chain-alkyl acrylate, and a polar monomer.
2. The coating composition of claim 1 wherein said fluorinated
polymer has a molecular weight of less than 250,000.
3. The coating composition of claim 1 wherein said fluorinated
polymer has a molecular weight between 5,000 and 120,000.
4. The coating composition of claim 1 wherein the fluorinated
polymer is the acrylic reaction product of at least three polymers
comprising at least one fluorinated acrylate, at least one
short-chain-alkyl acrylate, and at least one polar monomer.
5. The coating composition of claim 4 wherein said fluorinated
polymer has a molecular weight of less than 200,000.
6. The coating composition of claim 1 wherein the polymer
compatible with said solvent is selected from the group consisting
of polyvinyl acetals, polyacrylates, polyurethanes,
acrylated-urethanes, polyozlactones, polyvinyl resins,
phenol-formaldehyde resins, mophtroguinone-diazides, polyamides,
and mixtures thereof.
7. A coated surface comprising a substrate with at least one
surface having a coating thereon comprising an organic polymer and
a fluorinated polymer, said fluorinated polymer comprising the
acrylic reaction product of at least one fluorinated acrylate, a
short-chain-alkyl acrylate, and a polar monomer.
8. The coated surface of claim 7 wherein said substrate comprises a
polymeric film.
9. The coated surface of claim 7 wherein said substrate comprises
polyethylene terephthalate.
10. The coated surface of claim 7 wherein said substrate comprises
aluminum.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the use of fluorochemical
surfactants in coating compositions to reduce disuniformities in
the coatings. The surfactants reduce such effects as mottling
without causing such side effects as fisheye and foaming in the
coated materials. These surfactants are particularly useful in
graphics systems such as positive-acting or negative-acting resist
systems including printing plates and non-resist imageable
polymerizable systems.
2. Background of the Art
There are many different types of coating operations that use
organic polymeric resins in the coating solutions. The polymers are
normally coated out of a solid solution and dried by the removal of
most of the solvent. Many of the defects and problems that occur in
the final product can be attributable to phenomena that occur in
the coating and drying procedures. Amongst the problems that are
known to occur during drying of polymeric film layers after coating
are unevenness in the distribution of solid materials within the
layer. Examples of specific types of problems encountered in
coatings are "orange peel" and "mottling." The former is a fairly
regular grainy surface that occurs on a dried coated film, usually
because of the action of the solvent on the materials in the
coating composition. Mottling often occurs because of an unevenness
in the removal of the solvent from the coating composition.
"Fisheyes" are another type of coating problem, usually resulting
from a separation of components during drying. There are pockets of
different ingredients within the drying solution, and these pockets
dry out into uneven coating anomalies.
Surfactants have often been used to correct these types of
problems, along with changes in the solvents of the coating
compositions. Sometimes surfactants do not correct the salient
problem, and in other cases, the surfactants create other problems
even when they cure the first. It is sometimes necessary to
investigate a large number of commercially available surfactants
before finding one that is appropriate for a particular type of
system, even if that commercial product is touted for use in
correcting a particular type of defect.
U.S. Pat. Nos. 4,764,450 and 4,853,314 describe the use of
particular changes in solvent systems to improve surface defects in
positive-acting photoresist imaging systems.
U.S. Pat. No. 4,557,837 describes fluorochemicals useful in the
preparation of foamable compositions such as those used in the
cleanup of gas wells. The polymers described within that patent
include some compounds useful in the practice of the present
invention.
U.S. Pat. No. 3,950,298 describes thermoplastic fluorinated
terpolymers that are useful, non-foaming additives to coating
solutions for polymeric materials such as carpets and fibers. The
coating compositions provide oleophobicity to the surfaces that are
coated.
SUMMARY OF THE INVENTION
Fluorinated polymers formed by the polymerization of at least three
monomers can provide a non-foaming or low foaming surfactant that
is particularly useful in the application of polymerics layers. The
surfactants can reduce surface anomalies such as mottling and
fisheyes in certain solvent systems. The at least three monomers
comprise a fluorinated ethylenically unsaturated monomer, a short
chain-alkyl ethylenically unsaturated monomer, and a polar
ethylenically unsaturated monomer.
DETAILED DESCRIPTION OF THE INVENTION
The present invention describes a coating composition comprising an
organic solvent, an organic polymer compatible with said solvent,
and a coating aid comprising a fluorinated polymer different from
said polymer compatible with said solvent, said fluorinated polymer
having at least three different moieties within the polymer chain
derived from reactive monomers, the moieties comprising a
fluorochemical acrylate, a short-chain-alkyl acrylate, and a polar
monomer.
The present invention relates to polymeric surfactants which are
particularly useful in the formation of polymer coatings, most
particularly in the formation of imageable media where surface
anomalies must be kept to a minimum. The fluorinated polymers
contain at least three different units derived from at least three
different copolymerizable monomers. The monomers would at least
comprise a fluorinated ethylenically unsaturated monomer, a
short-chain alkyl ethylenically unsaturated monomer, and a polar
ethylenically unsaturated monomer. The polymers can be most
conveniently formed by generating a polymeric backbone with the
required pendant functionalities thereon. This can be done
conveniently by selecting appropriate ethylenically unsaturated
monomers with the desired pendant functionalities already present
on the monomers so that they are also deposited on the polymer
backbone. This is preferably done by forming an acrylate backbone
by polymerization of at least three materials. Fluorochemical
acrylate, short-chain alkyl acrylate, a polar monomer (e.g.,
acrylic acid). As previously noted, acrylates are not the only
materials that will work, but they are preferred. The
fluorochemical acrylate comprises an acrylate (including
methacrylates) having a fluorocarbon group bonded to a hydrocarbon
portion of the acrylate. The bonding of the group may be directly
to the hydrocarbon group or bridging group on the acrylate, or it
may be through an additional bridging group such as a sulfonamide
group. These three monomers are free radically polymerized in the
proportions desired for the final product. The polymerization is
done in solvent, such as ethyl acetate or other convenient
solvents. The short-chain alkyl acrylates have fewer than eighteen
carbon atoms in the alkyl chain. Preferably the alkyl chain has
fewer than sixteen carbon atoms, and more preferably less than
twelve carbon atoms. The polar monomer for use in the present
invention must have a polymerizable group compatible with acrylic
polymerization, i.e., have ethylenic unsaturation as would be the
case in an acidic styrene derivative. The preferred polar monomers
are acidic monomers of acrylates (including methacrylates) and
particularly those at least as polar and preferably more polar than
hydroxyethylmethacrylate(HEMA). Although all molecular weights were
found to reduce mottling, higher molecular weights could increase
the foaming of the solutions. It was therefore found that molecular
weights of less than 250,000 (weight average molecular weight) and
more preferably less than 200,000 are desired. The most preferred
materials had weight average molecular weights in the range of
15,000 to 120,000 (approximately 25,000 to 95,000).
Representative ethylenically unsaturated polar comonomers useful in
such preparation include:
CH.sub.2 .dbd.CHCOOCH.sub.2 CH.sub.2 OH, CH.sub.2
.dbd.CHP(O)(OH).sub.2,
CH.sub.2 .dbd.CHCOOH, CH.sub.2 .dbd.C(CH.sub.3)COOH,
HOOC(.dbd.CH.sub.2)CH.sub.2 COOH, CH.sub.2 .dbd.CHSO.sub.3 H,
CH.sub.2 .dbd.CHCH.sub.2 SO.sub.3 H, CH.sub.2
.dbd.CHCONHC(CH.sub.3).sub.2 CH.sub.2 SO.sub.3 H,
and combinations thereof.
Representative fluoroaliphatic vinyl monomers useful in such
preparations include:
C.sub.8 F.sub.17 CH.sub.2 CH.sub.2 N(Ch.sub.3)COCH.dbd.CH.sub.2,
C.sub.8 F.sub.17 CH.sub.2 CH.sub.2 OCOCH.dbd.CH.sub.2, C.sub.6
F.sub.13 C.sub.2 H.sub.4 SCOCH.dbd.CH.sub.2, C.sub.8 F.sub.17
SO.sub.2 N(C.sub.2 H.sub.5)C.sub.2 H.sub.4 NHCOCH.dbd.CH.sub.2,
(CF.sub.3).sub.c CF(CF.sub.2).sub.8 C.sub.2 H.sub.2
SCOC(CH.sub.3).dbd.CH.sub.2, C.sub.8 F.sub.17 SO.sub.2
N(CH.sub.3)C.sub.2 H.sub.4 COOCH.dbd.CH.sub.2, C.sub.8 F.sub.17
SO.sub.2 N(CH.sub.3)CG.sub.2 C.sub.6 H.sub.4 CH.dbd.CH.sub.2,
C.sub.6 F.sub.13 CH.sub.2 CH.sub.2 OOCC(.dbd.CH.sub.2)COOCH.sub.2
CH.sub.2 C.sub.6 F.sub.13, C.sub.7 F.sub.15 CH.sub.2
OOCCH.dbd.CHCOOCH.sub.2 C.sub.7 F.sub.15, C.sub.6 F.sub.13 C.sub.2
H.sub.4 N(CH.sub.2 CH.sub.2 OH)COCH.dbd.CH.sub.2, C.sub.7 F.sub.15
CON(C.sub.2 H.sub.5)C.sub.3 H.sub.6 SCOC(CH.sub.3).dbd.CH.sub.2,
C.sub.6 F.sub.13 CH.sub.2 NHCOCH.dbd.CH.sub.2, C.sub.8 F.sub.17
CH.sub.2 CH.sub.2 OCH.dbd.CH.sub.2, (CF.sub.3).sub.2
CF(CF.sub.2).sub.6 CH.sub.2 CH(OH)CH.sub.2 OCOCH.dbd.CH.sub.2,
(CH.sub.3).sub.2 CFOC.sub.2 F.sub.4 OCOCH.dbd.CH.sub.2, C.sub.8
F.sub.17 C.sub.2 H.sub.4 SO.sub.2 N(C.sub.3 H.sub.7)C.sub.2 H.sub.4
OCOCH.dbd.CH.sub.2, C.sub.7 F.sub.15 C.sub.2 H.sub.4 CONHC.sub.4
H.sub.8 OCOCH.dbd.CH.sub.2, ##STR1## C.sub.7 F.sub.15 COOCH.sub.2
C(CH.sub.3).sub.2 CH.sub.2 OCOC(CH.sub.3).dbd.CH.sub.2, C.sub.8
F.sub.17 SO.sub.2 N(C.sub.2 H.sub.5)C.sub.4 H.sub.8
OCOCH.dbd.CH.sub.2, (C.sub.c F.sub.7).sub.2 C.sub.6 H.sub.3
SO.sub.2 N(CH.sub.3)C.sub.2 H.sub.4 OCOCH.dbd.CH.sub.2, C.sub.8
F.sub.17 CF.dbd.CHCH.sub.2 N(CH.sub.3)C.sub.2 H.sub.4
OCOCH.dbd.CH.sub.2,
and combinations thereof.
The polymers useful in the present invention comprise any polymer
soluble or dispersible in the organic solvent, particularly methyl
ethyl ketone, 1-methoxy-2-propanol, and 30/70 mixtures of MEK and
1-methoxy-2-propanol. Examples of useful resins and polymers are
polyvinyl acetals (e.g., polyvinyl butyral, polyvinyl formal),
polyacrylates (e.g., from acrylates, methacrylates, acrylic acid,
methacrylic acid, alkylacrylates, alkymethacrylates, etc.),
polyurethanes, acrylated-urethanes, polyazlactones, polyvinyl
resins (e.g., polyvinyl acetate, polyvinyl chloride, copolymers of
vinyl resins, e.g., VAGH, VNYH, etc.), naphthogurnone-diazides,
phenol-formaldehyde resins, polyamides, and mixtures thereof.
EXAMPLE 5
A random tertpolymer of Et-FOSEMA/BuMA/Acrylic Acid was prepared by
dissolving 10 g Et-FOSEMA (FX-14, 3M), 6 g butyl methacrylate (Rohn
& Haas), 4 g acrylic acid (Aldrich Chem, Milwaukee, WI), 0.8 g
of Trigonox 21-C50 (50% t-butyl peroctoate, Witco Corp, a
subsidiary of Akzo Corp) in 47 g of ethyl acetate. The
polymerization solution was purged with nitrogen through a dip tube
for two minutes and then sealed. The sealed bottles was shaken at
78.degree. C. for eighteen hours. At the end of eighteen hours, the
bottle was cooled down to room temperature and air was admitted.
Polymer solution (2.1 g) was dried in a small aluminum pan at
90.degree. C. for 1 hour. At the end of this time, 0.6 g of dry
brittle solid was left (28.6% solids). When the polymer solution
was diluted with 30/70 Dowanol.TM. PM/MEK (Dowanol.TM. PM,
1-methoxy-2-propanol solvent sold by Dow Chemical Co. and methyl
ethyl ketone) to 0.05% surfactant. The surface tension was found to
be 23.0 dynes/cm as measured by a Wilhemy plate. Yellow pigment was
dissolved in the 0.05% FC surfactant solution at the 12% solids
level. This solution was shaken twenty times and the time it took
for the foam level to fall to zero was found to be 4 minutes 30
seconds. The solution (30/70 Solv PM/MEK) of yellow pigment (2%
solids) with 0.05% of the FC polymer described above (based on
solid polymer dissolved in ethyl acetate solution at 28.6% by
weight) was coated on PET (polyethylene terephthalate) by pulling a
hand spread on a wire wound rod (Meyer bar). The coated PET was
dried under controlled air velocity and temperature conditions (in
a forced air drying oven), then evaluated using a subjective
comparison test with other similar formulations. Materials coated
out showed approximately 75% less mottle than a control with no
surfactant according to the present invention.
The table below shows the experiments listed as examples and their
composition. Et-FOSEMA is an abbreviation for N-ethyl
perfluorooctanesulfonamidoethyl methacrylate [C.sub.8 F.sub.17
N(C.sub.2 H.sub.5)CH.sub.2 CH.sub.2 OCOC(CH.sub.3).dbd.CH.sub.2 ].
FOMA is an abbreviation for 1,1-dihydroperfluorooctyl methacrylate
[C.sub.7 F.sub.15 CH.sub.2 OCOC(CH.sub.3).dbd.CH.sub.2 ].
Comparative Examples whose composition does not lie within the
definition of the invention as described in the first section are
listed below in Table 2. C-1, C-2, and C-3 use a higher alkyl
methacrylate (eighteen carbons) instead of a lower alkyl one (one
to ten carbons). C-3 uses a higher mole fraction of fluorochemical
acrylate (0.80) in the polymer than as defined by this invention
(less than 0.30). C-4 uses a lower mole fraction (X) of
fluorochemical (x=0.085) than as defined by the preferred mode of
this invention (x=greater than 0.089). Y is the mole fraction of
the short-chain alkyl methacrylate and z is the mole fraction of
the polar monomer. X+Y+Z is equal to N less than 1.0. C-5, C-3, and
C-2 violate the preferred mode of this invention that X+Z should be
less than 0.65 (see Table 3). It is preferred that X is above 0.085
and 0.30, Y should be between 0.10 and 0.615 or less, and Z should
be between 0.30 and 0.60.
TABLE 1 ______________________________________ Monomer Composition
of Examples Weight % Example Et-FOSEMA .COPYRGT./MA*/AA
______________________________________ 1 36/48 BuMA/16 2 29 FOMA/55
BuMA/18 3 28/60 LMA 12 4 40/35 BuMA/25 5 50/30 BuMA/20 6 47 FOMA/38
BuMA/14 7 55/35 BuMA/10 8 50/50 BuMA/0 9 50 FOMA/50 BuMA/0 10 55/35
BuMA/10 11 55/35 BuMA/10 12 55/35 BuMA/10 13 55/35 BuMA/10
______________________________________
TABLE 2 ______________________________________ Monomer Composition
of Comparative Experiments Weight % Example Et-FOSEMA
.COPYRGT./MA*/AA ______________________________________ C-1 (Comp)
50/50 ODMA/0 C-2 (Comp) 50/ODMA/20 C-3 (Comp) 80/12 ODMA/18 C-4
(Inv) 40/40 MMA/20 C-5 (Inv.) 60/20 MMA/20
______________________________________
Examples 1, 2, 3, 6, 7, 8, 9 were prepared in the following
manner.
A random tertpolymer of Et-FOSEMA or FOMA/alkyl
methacrylate/Acrylic Acid was prepared by dissolving the
appropriate amount of Et-FOSEMA or FOMA, alkyl methacrylate and
acrylic acid, so that the total weight of monomers charged was 20
g, and 0.8 g of Trigonox 21-C50 (50% t-butyl proctoate, Witco Corp,
a subsidiary of Akzo Corp) in 113 g of ethyl acetate. The
polymerization solution was purged with nitrogen through a dip tube
for two minutes and then sealed. The sealed bottles was shaken at
78.degree. C. for eighteen hours. The bottle was then cooled down
to room temperature and air was admitted.
EXAMPLES 4, 5, 12, C-2, C-3, C-5
These materials were prepared as outlined in Example 1 above so
that the total weight of monomers charged in each case was 20
g.
EXAMPLE 11
A random terpolymer of Et-FOSEMA/BuMA/Acrylic Acid was prepared by
dissolving 11 g of Et-FOSEMA, 7 g butyl methacrylate, 2 g acrylic
acid, 0.1 g dodecyl mercaptan, and 0.8 g of Trigonox 21-C50 in 113
g of ethyl acetate. The polymerization solution was purged with
nitrogen through a dip tube for two minutes and then sealed. The
sealed bottles was shaken at 78.degree. C. for eighteen hours. The
bottle was then cooled down to room temperature and air was
admitted.
EXAMPLE 2
A random terpolymer of Et-FOSEMA/BuMA/Acrylic Acid Was prepared by
dissolving 304 g of Et-FOSEMA, 195 g butyl methacrylate, 56 g
acrylic acid, 2.7 g dodecyl mercaptan, and 22 g of Trigonox.TM.
21-C50 (50% t-butyl peroctoate) in 1283 g of ethyl acetate. The
polymerization solution was purged with nitrogen by allowing
nitrogen to flow through the flask for 30 minutes while the
monomers and solvent were charged. A slight positive nitrogen
pressure was maintained on the flask during the reaction. The
reaction mass was stirred at 75.degree.-81.degree. C. for 6.5
hours. At the time air was admitted to the flask and the solution
was allowed to cool down to room temperature. The viscosity of the
reaction mixture was measured and found to be 9.3 centistokes.
EXAMPLE 13
A random terpolymer of Et-FOSEMA/BuMA/Acrylic Acid was prepared by
dissolving 36 g of Et-FOSEMA, 88 g butyl methacrylate, 25.2 g
acrylic acid, and 9.9 g of Trigonox 21-C50 (50% t-butyl peroctoate)
in 400 g of ethyl acetate. The polymerization solution was purged
with nitrogen by allowing nitrogen to flow through the flask for 30
minutes while the monomers and solvent were charged. A slight
positive nitrogen pressure was maintained on the flask during the
reaction. The reaction was stirred at 75.degree.-83.degree. C. for
6.5 hours. At that time air was admitted to the flask and it was
allowed to cool down to room temperature. The viscosity of the
reaction mixture was measured and found to be 2.09 centistokes. The
weight % unreacted monomers in the polymer as determined by
gravimetric chromatography of standard solutions was found to be
0.35% Et-FOSEMa, 0.33% butyl methacrylate, 0.4% acrylic acid. H-nmr
and C-nmr (Anal Req 37607) were consistent for the desired
polymer.
TABLE 3 ______________________________________ Foam Collapse Time
Time for Foam Col- Wt % lapse (Minutes-m, Ex # Et-FOSEMA
.COPYRGT./MA*/AA Seconds-s) x + z
______________________________________ C-2 50/50 ODMA/20 >15 m
0.80 C-3 80/12 ODMA/18 >15 m 0.91 C-5 60/20 MMA/20 >15 m 0.65
4 40/48 BuMA/16 4 m 30 s 0.57 5 50/30 BuMA/20 4 m 30 s 0.63 6 47
FOMA/38 3 m 0.52 BuMA/14 9 50 FOMA/50 BuMA/0 3 m 0.23 2 29 FOMA/55
2 M 15 s 0.45 BuMA/18 1 36/48 BuMA/16 2 m 0.48 3 28/60 LMA/12 1 m
45 s 0.45 8 50/50 BuMA/0 1 m 45 s 0.18 C-4 40/40 MMA/20 1 m 24 s
0.44 7 55/35 BuMA/10 1 m 15 s 0.45 no FC surfactant 1 m
______________________________________
As can be sen in Table 3, foam times of less than 5 minutes were
obtained when the sum of the mole fractions of fluorochemical
monomer plus acrylic acid were less than 0.65. Compositions where
x+z were 0.65 or greater, all had foam times of 15 minutes or
greater.
* * * * *